Field of the Invention
The present invention relates to an electrophotographic member for use in an electrophotographic apparatus, and a process cartridge and an electrophotographic apparatus having the electrophotographic member.
Description of the Related Art
An electrophotographic member is used in various applications, for example, as a developer carrying member, a transfer roller, a charging roller or a cleaning blade. Such an electrophotographic member can have an electrical resistivity of 103 to 1010 Ω·cm. As a method for controlling the resistance of such an electrophotographic member, for example, a measure is generally used in which an ion conductive agent is included in a resin layer of an electro-conductive roller. However, when the ion conductive agent is included in the resin layer, the ion conductive agent may leak out from the surface of the electro-conductive roller. When the ion conductive agent leaks out, the ion conductive agent may contaminate other member abutting with or adjacent to the electro-conductive roller, causing image failures.
For example, when the electro-conductive roller is a developer carrying member, the ion conductive agent that has leaked out may be attached to the surface of a photosensitive member, thereby to reduce the electrical resistance on the surface of the photosensitive member, which increases the image density corresponded to the area, and impairs the uniformity in image density.
In order to avoid such problems, a method was recently proposed in which the ion conductive agent is immobilized to the resin layer.
For example, in Japanese Patent Application Laid-Open No. 2007-297438, an electro-conductive roller in which an ion conductive agent having one hydroxyl group is used to thereby allow the ion conductive agent to be immobilized to a urethane resin was proposed.
In addition, in Japanese Patent Application Laid-Open No. 2011-118113, an electro-conductive roller in which an ion conductive agent having two hydroxyl groups is used to thereby allow the ion conductive agent to be immobilized to a urethane resin was proposed.